Draft gear



Oct. 18, 1932. J. M. HALL 1,882,832

DRAFT GEAR Filed Feb. 19, 1930 4 Sheets-Sheet l lijuantofi \fosz vhfi H016 4 F MM////// J. M. HALL Oct. 18, 1932.

DRAFT GEAR Filed Feb. 19. 1930 ll mlvi w 4h W 3 2 2 J. M. HALL DRAFT GEAR Oct., 18, 1932.

Filed Feb. 19, 1950 4 Sheets-Sheet Patented Oct. 18,1932

E OFFICE JOSEEI 1&1. HALL, OF CHICAGO, ILLINOIS,,ASSIGNOR TO UNIVERSAL DRAFT GEAR ATTACHMENT 00., A CORPORATION OF ILLINOIS DRAFT GEAR Application filed February 19, 1930. Serial No. 429,498.

The invention relates to the type of draft gear in which the spring resistance is supplemented byv the friction of a plate, movable with the spring and clamped between elements movable with the opposed follower vand urged towardthe plate by the action of clamping elements upon the plate.

An embodiment of the invention, subject to various modifications within its scope, is hereinafter described and is illustrated in the accompanying drawings, in which Fig. 1 is a central, longitudinal, vertlcal section of the gear;

Fig. 2 is a plan view of the improved fric tion plate and associated parts, some of the parts being fragmentarily shown;

F 3 and 4 are sectional views on the lines 33 and ll respectively of Fig.1, 7 5

Fig; 5 is a view, partly in elevation and partly in section, on the broken line 55 of e- Fig. 6 is a sectional view on thebroken line 6--6ofFig.1;

Fig.7 is detail in elevation of various of the elements of the gear; and I Fig. 8 is a detail in perspective of the same elements and others associated therewith.

The gear as illustrated comprises a chambered follower 10 and an opposed plate follower 11. Within the follower 10, there is housed a spring or springs 12 which react between the closed end of the follower and a pring seat or floating follower 13. Two

groups of intercalated friction plates are hou within the open end of the follower 10, one set as 14, 15 of ach group being anchored longitudinal movement to a h :llZOlltZll wall of the follower; the other set of plates of each group, as 16, 17, being floating plates'and normally projecting beyond the open end of the follower and also beyond the inner ends of the anchored plates. One or more plates of each group is tapered to ward its forward or outer end. As shown, this form is given only to the inner anchored plate 15. Preferably, a wear plate 18 is secured to each of the side walls of the follower 10 and is frictionally engaged by the outer plate 16 of the floating set.

A pair of thrust or pusher elements 19, 20

is seated against the plate follower 11 and between them is clamped a friction plate21 which has bearing at its inner end against the floating follower or spring seat 13.

In the following description and in the appended claims, the words inner inwardly and outwardly have reference to the longitudinal axis of thegear and the word forwardly to the direction of thrust as the gear is compressed.

The inner ends of the thrust elements 19, 20 are inwardly and forwardly inclined to form wedge faces 22 and against each of these faces isseated the end of a wedging friction shoe 23, such end being correspondingly in:

clined. The outer faces of the shoe 23 frictionally engage the inner plate, as 15, of one of the sets of intercalated plates, and its inner end is beveled or inclined forwardly and outwardly as'shown at 24:, forming a wedging face for engaging the complementar faces 25 on an element here shownin the ormiof a bar 26, which has upon its forward face a wedging surface 27 cooperating with an inclined shoulder or wedge surface 28 formed on the head 29 of the plate 21. Eachof the elements 19, 20 is provided with a forwardly extending bifurcated arm 30, the inner face of which is a continuation of the inner face of the thrust element. The inner end of the arm 30 is forwardly and inwardly inclined to form the wedge face 31 and preferably this portion of the arm is laterally extended, as

' shown in Fig. 8. The bar 26 is provided with a wedge face 32 engaging the wedging face 31. For convenience in assembling the gear elements, the anchoring wings 34 of the relatively stationary friction plates 15, which at their inner ends abut against integral shoulders as 35 formed on the wallof the chambered follower, are engaged lay-removable retaining blocks 36 which seat against shoulders as 37 formed on the same wall and adjacent the open end of the follower.

The relatively movable plates, as 17, may be inserted after the blocks 36 have been-in V the spring. As hie shoes 23 slide tIOC uced, and their width is such as to prevent the dislodgnient of these blocks from the shoulders 37. The head 29 of the plate 21 is elongated beyond the margins of the plate, and its inner face is preferably rounded, as indicated at 38, and seats against a rounded surface 39 of the spring seat 13.

The inner face of each of the friction shoes 23 is provided with a longitudinal rib 10, which fits between the twobranches of the bifurcated arm 30, the parts being thereby held against lateral displacement.

The inner or adjacent faces of the thrust elements 19, 20, and preferably of the arm '30, extending forwardly therefrom, are inclined, and the faces of the plate 21 are similarly inclined. Preferably these several faces are stepped or subdlvided into a plurality of inclines, as 41, 42, 43, 1 1, having greater pitch relatively to the longitudinal axis of the gear than could be secured by a continuous in clined face extending through the entire length of the element upon which it is formed.

The various wedging faces of the elements 19, 20, 23, 26 and 29 are quite blunt, or obtuse to the axis of the gear, so that the two followers approach each other on the compression of the these wedging elements act substantially as a column for compressing along the faces of the plates 15 they are forced inwardly by the wedging action of the tapered plat-es, and thereby lengthen the column and "urgelthe thrust elements 19, 20, and their extensions against the plate 21, which plate is carried forwardly as the column is lengthened against the frictional resistance between it'and the thrust elements.

It has been found in practice that when in this t e of "ear a con" al friction late of uniform thickness is employed, excessive friction is developed and the free action of the gear both on compression and release is prevented. The tapered form of the central friction plate 21, and of the faces of the thrust elements with whichit cooperates, reduces this friction in proportion to the degree of the taper.

The stepped form,as described, permits a greater inclination of the contacting surfaces and provides for a better regulation of the friction without reducing the aggregate area of frictional contact. Normally the floating friction plates 16, 17, are out of engagement with the follower 11. The elongation of the column interposed between the follower 11 and spring seat 13 beginspromptly upon the inception of the compressive movement, and the seat 13 is carried away from the inner ends of the plates 16, 1?, with which it is normally in engagement. As the compres sion continues the follower makes contact with the plates 16, 11'', and forces them inwardly. .Upon release the group of wedging elements, including the shoes 23 and the centrail friction plate, are urged toward normal position by the action of the spring 12, the plates 16, 17, being carried outwardly as soon as the spring seat 13 comes into engagement with them. The acute angle of the tapered plates 15 permits a free action upon release.

WVhile the lateral inward pressure upon the friction shoes is gradually relieved as the release progresses, a too abrupt release is prevented by the wedging action of the tapered central plate 21 upon the thrust elements 19, 20, thereby maintaining the shoes in engagement with the tapering plates and retarding the release by the friction there developed.

The elements 26 are introduced mainly for the purpose of taking up slack due to wear of the various friction surfaces. The normal action of the gear would be the same if the wedging action were communicated directly from the shoes 23 to the arms 30 and the head 29, instead of through the elements 26.

I claim as my invention:

1. In a draft gear in combination, a chambered follower, an opposed follower, a follower within the chamber, a spring reacting between the last named follower and the end of the chambered follower, a pair of thrust elements, seated against the opposed follower, their inner faces being forwardly and outwardly inclined, a thrust element associated with the outer face of the spring advanced follower and having a stem located between the pair of thrust elements, such stem having faces complementary to the inclined faces thereof, wedge means for advancing the second named thrust element in opposition to the spring up on movement of said first named thrust elements and for forcing the pair of first named thrust elements against the stem, said wedge means also causing relative movement of the stem and the first named thrust elements.

2. In a draft gear in combination, a chambered follower, an opposed follower, two groups of intercalated friction plates, one set of each group being longitudinally anchored to the chambered casing, the other set being floating and normally projecting from the open end of the casing, one plate of each group being tapered, a pair of thrust elements seated against the opposed follower, their adjacent faces having forwardly and outwardly inclined surfaces and their forward faces being forwardly and inwardly inclined, a spring seat within the chambered follower and being engageable with the inner ends of the floating plates, a spring reacting between the seat and the closed end of the first named follower, a plate interposed between the thrust elements and having inclined surfaces complementary to the inclined surfaces thereof, such plate having bearing against the spring seat and having lateral rearwardly facing shoulders near its inner 3. In a draft gear in combination, a chambered follower, an opposed follower, two groups of lntercalated friction plates, one

set of each group being longitudinally ans chored to the chambered follower, the other set being floating and normally projecting from the open end of such follower, one plate of each group being tapered, a pair of thrust elements seated against the opposed follower having forwardly projecting arms, the adjacent faces of the elements and their arms having forwardly and outwardly inclined surfaces and their forward faces being forwardly and inwardly inclined, a spring seat within the chambered follower and bein engageable with the inner ends of the floating plates, a spring reacting between the seat and the closed end of the first named follower, a plate interposed between the thrust elements and having inclined surfaces complementary to the inclined surfaces thereof, such plate having bearing against the spring seat and having lateral rearwardly facing shoulders near its inner end, and wedging elements interposed between the thrust elements and th plate shoulders, and bearing laterally against the friction plates.

4. In a draft gear in combination, a chambered follower, an opposed follower, two groups of intercalated friction plates, one set of each group being longitudinally anchored to the chambered follower, the other set being floating and normally projecting from the.

open end of such follower, one plate'of each group being tapered, a pair of thrust elements seated against the opposed follower, their adj acent faces having forwardly'and outwardly inclined surfaces and their forward faces being forwardly and inwardly inclined, a spring seat within the chambered follower and being engageable with the inner ends of the floating plates, a spring reacting be tween the seat and the closed end of the first named follower, a plate interposed between the thrust elements and having incline-d surfaces complementary to the inclined surfaces thereof, such plate having bearing against the spring seat and having lateral rearwardly facing wedging shoulders near its inner end, and wedging elements interposed between the thrust elements and the'plate shoulders and bearing laterally against the, friction plates.

5. In a draft gear in combination, a charm bered follower, an opposed follower, two groups of intercalated friction plates, one set of each group being longitudinally anchored to the chambered follower, the other set being floating and normally projecting from the open end of such follower, one plate of each group being tapered, a pair of thrust elements seated against the opposed follower,

their adjacent faces having forwardly and outwardly inclined surfaces and their forward faces being forwardly and inwardly inclined, a spring seat within the chambered follower 'and being engageable with the inner ends of the floating plates, a spring reacting between the seat and the closed end of the first named follower, a plate interposed between the thrust elements and having inclined surfaces complementary to the inclined surfaces thereof, such plate having bearing against the spring seat and having lateral rearwardly facing shoulders near its inner end, and wedging friction shoes cooperating with the wedging faces ofthe pair of thrust elements and with the shoulders of the interposed plate and bearing laterally against the groups of plates.

6. In a draft gear in combination, a chambered follower, an opposed follower, two groups of intercalated friction plates, one set of each group being longitudinally anchored to the chambered follower, the other set being floating and normally projecting from the open end of such follower, one plate of each group being tapered, a pair of thrust elements seated against the opposed follower, their adjacent faces having forwardly and outwardly inclined surfaces and t ieir forward faces being forwardly and inwardly inclined, a spring seat within the chambered follower and being engage'able with the inner ends of the floating plates, a spring reacting between the seat an the closed end of the first named follower, a plate interposed between the thrust elements and having inclined surfaces complementary to the inclined surfaces thereof, such plate having bearing against the spring seat and having lateral'rearwardly facing shoulders near its inner end, and wedging friction shoes cooperating with the wedging faces of the pair of thrust elements and with the shoulders of the interposed plate and bearing laterally against the groups of plates, and wedging elements interposed between the shoes and the plate shoulders.

7 In a draft gear in combination, a chambered follower, an opposed follower, two groups of intercalat-ed friction plates, one set of each group being longitudinally anchored to the chambered follower, the other set being floating and normally projecting from the open end of such follower, one plate of each group being tapered, a pair of thrust elements seated against the opposed follower and having forwardly projecting arms, the adjacent faces of the elements and their arms having a longitudinal series of forwardly and outwardly inclined surfaces and their forward faces being forwardly and inwardly inclined, a spring seat within the chambered follower and being enga'geable with the inner ends of the floating plates, a spring reacting between the seat and the closed end of the first named follower, a plate interposed between the ill thrust elements and having inclined surfaces complementary to the inclined surfaces thereof, such plate having bearing against the spring seat and having lateral rearwardly facing shoulders near its inner end, and wedging elements interposed between the thrust elements and the plate shoulders and bearing laterally against the friction plates.

In testimony whereof I aflix my signature.

JOSEPH M HALL. 

